Fluorescent tube luminaires are widely used for illumination of e.g. commercial office spaces, schools, and lab facilities. Such luminaires are often arranged in a dropped ceiling, i.e. a secondary ceiling hung below the main, structural ceiling. A dropped ceiling may consist of a metal grid structure defining regularly spaced cells, e.g. having the dimensions of 2×4, 2×2 or 1×4 feet, which cells can be filled with tiles or panels so as to provide a flat surface hiding the space above the dropped ceiling.
A fluorescent tube luminaire may be accommodated in a cell of the dropped ceiling. In general, the luminaire may comprise a lighting fixture, or troffer, and optical elements enabling a desired optical performance. The luminaire may be recessed above the dropped ceiling grid and adapted to accommodate one or several fluorescent tubes. It is also common to provide light fixtures that fit the same space as a tile in order to facilitate installation.
Today, there is a growing demand for replacing fluorescent tubes with less energy consuming illumination devices, such as e.g. light emitting diode (LED) based illumination devices. Aspects of a kit for replacing fluorescent tubes in a fluorescent tube luminaire with a plate-like LED based lighting system are discussed in JP 2013/118063. That document describes a LED system that makes use of existing light fixtures, wherein the fluorescent tubes are replaced with two rods that are fixated to the sockets of the fixtures. A flat LED unit is then attached to the light fixture by means of L-shaped hooks that engage with the rods.
Although such LED-lighting systems can be used for replacing fluorescent tubes, there is still a need for improved kits that are easier to install in the lighting fixture.